Select the most appropriate ANTONYM of the underlined word.

Her dog can climb under the fence.

The correct option is Over.

Step-by-step Explanation:

1. Analyze the underlined word: The word underlined in the sentence is under. "Under" is a preposition that indicates a position below or beneath something (in this case, the fence).

2. Understand the requirement: We need to find the antonym (the word opposite in meaning) of "under".

3. Evaluate the options:
- Over: This preposition means at a higher level than or above something. This is the direct opposite of being below or under something.
- Sink: This is a verb meaning to go down below the surface, which is not an antonym of "under".
- Behind: This indicates a position at the back of something.
- Beneath: This is a synonym of "under", meaning directly under or lower than.

Therefore, the direct antonym of "under" is Over.